Disk grinder.



J. A. McINTOSH.

I ms1 GRINDER. APPLICATION FILED NOV. 19, 1915' 1,235,708. Patented Aug. 7, 1917.

3 SHEETS-SHEET I.

J A. MclNTOSH. DISK GRINDER.

APPLICATION FILED NOV. 19, I915- Patented Aug. 7, 1917.

J. A. McINTOSH.

DISK GRINDER. APPLICATION FILED NOV. 19. I9 l5- Patented Aug. 7, 1917.

3 SHEETSSHEET 3- JOHN A. MoINTOSI-I, or CHICAGO, ILLINOIS.

DISK GRINDER..-

\ Specification of Letters Patent.

' Patented Aug. v, 1917.

Application filed November 19, 1915. Serial No. 62,291.

' To all whom it may concern:

Be it known that I, JOHN A. MCINTOSH,

.a citizen of the United States, residing at Chicago, in the county of Cook and 'State of Illinois, have invented new andfuseful Improvements in Disk Grinders, of which the following is a specification, reference being had to the accompanying drawings, forming a part thereof.

This invention relates to improvements in disk grinders or sandpaper wheels such as are used by pattern makers, and is principally concerned with the adjustable mounting of the work table and work-holding de- I vices thereon.

In'the drawings Figure 1 is a side elevation of a grmding machine embodying this invention.

Fig. 2 is a front elevation of the upper portion of the machine shown in Fig. 1.

Fig. 3 is a partial plan view showing the grinding wheel or disk and its pulley, together with a portion of one of thework tables. Q

Fig. & is a detail section taken as indicated at line H on'Fig.3.

Fig. 5 is a detail section taken as indicated at theline 5-5 on Fig. 2.

Fig. 6 is a detail section taken as indicated at line 66 on Fig. 4.

Fig. 7 is a partial plan view similar to Fig. 3 but showing a different work-holding attachment on the table.

.Fig. 8 is a detail section taken as'indicated at line 88 on Fig. 7.

Fig. 9 is a detail section taken as indicated at line 99 on Fig. 7.

Fig. 10 is a plan view of a piece of work.

Fig. 11 is a detail section taken as indicated at. line, 1111, on Fig. 3.

- The machine illustrated herewith comprises essentially a base, 1, on which is mounted a frame, 2, providing journal bear-' ings, 3, for a rotary shaft, 4. The shaft is fitted with a drive pulley, 5, and awheel or disk, 6, to whose plain surface, 6*, is af fixed a sheet of sandpaper or similar abra sive material. Preferably, though not necessarily, themachine is made duplex by fitting two such disks, 6, to the shaft, 4:, one

at each end, and providing two work tables,

7, one for each disk, 6.

In use the abrasive material on the surface, 6*, of the disk, 6, becomes rapidly worn and must be frequently renewed... One of the features of this invention is concerned w 1th so mounting the work table, 7, and the dlsk, 6, as to permit of readily removing the latter for such renewal. The disk, 6, is preferably screwed on to the threaded end, l

of the shaft, 4, up againstthe shoulder, 4L-

The table, 7 ,is formed at each end with a semicircular flange, 7*, fitting into the curved, support, 8, which extends from the frame, 2; each of the flanges, 7 is itself formed with a flange, 7 overhanging the outer surface of the support, 8, for positioning the table thereon. The table, 7, is held upon the curved supports, 8, merely by its.

own weight, although clamping means are provlded as hereinafter explainedfor adjusting it angularly with respect to the face; 1'

of the disk, 6. Thus when it becomes necessary to renew the abrasive surface at 6 it is only necessary to lift off the table, 7, from the supports, 8, and unscrew the disk, 6, from the shaft, 4. I r I For much work,;particularly such as is encountered in a pattern shop, it is desirable that the table, 7, be inclined to the face of the disk, 6, and this is accomplished'by curving the flanges, 7 and the supports,.8, circularly about an axis in, or very close to, the surface, 6 such axis being preferably also a diameter of the disk, 6. Thus the supports, 8, form journal bearings in which the table, 7, is mounted to rotate through a limited range about an axis, practically inthe face of the disk, 6. To permit-such adjustment the edge, 7", of the table, 7, adjacent to the surface, 6, is beveled away from said surface to give sufficient clearance. The surface of the support, ,8, adjacent to theflange, 7 is provided with rotractor graduations, 8 and a zero mark, on the flange, 7', serves to indicate .ex-

actly the angle between the working surface.

of the table and the surface, 6 of the disk at any position ofadjustment. A clamping block, 9, hung on a stud, 10, with-its-notched end, 9, engaging the flange, 7 .serves to hold the table at adjusted position when the clamp wheel, 11, is screwed down along the threaded stud, 10., Fig. 5 shows a smaller 1 stud, 12, engaging the lower end of the block, 9, to checkit against rotation on the stud, 10, so that the notch, 9 will be always in position for clamping against the flange of the table, 7. It is only necessary to provide a clamp acting on one of the flanges, 7 5 the flange at the other end of the table, 7,

is formed with a notch, 7 adapted to receive the conical head, 18*, of a bolt, 13, hung in a lug, 8 of the support, 8. For bringing the table quickly to the position 10 at which its working surface stands at right angles to the surface, 6 of the disk, the bolt, 13, isheld up into contact with the flange, 7*, and the table, 7 is rotated until the bolt enters the notch, 7 (these parts being de- 5 signed for engagement at right angle position of the table), and the clamping wheel, 11, is then tightened up. As shown in Fig. 2 the bolt, 13, normally drops entirely out of range of the flange, 7", so as not to interfere with other adjustments.

A grinder of this type isfrequently used for shaping up circular pieces instead of turning them on a lathe. For this work the table, 7, is fitted with an attachment comprising a block, 14, having a tongue, 14 projecting from its under surface to fit the groove, 7 in the table surface; this secures the block, 14, at a fixed distance from the working face, 6, of the disk, 6, while permit ting some range of sliding movement across the face of the disk. The block, 14, is merely a frame in which is rotatably mounted a cir cular carrier, 15, which has a center pin, 16, fixed in it and projecting from its upper surface. By rotation of the carrier, 15, the pin, 16, may be moved toward and from the face, 6, of the disk, so that the work carried by the pin, 16, can be ground to the required radius. As indicated in dotted lines on Fig.

'40 3, the work is usually roughed out to an approximately cylindrical shape and is then driven down on to the center pin, 16. If a circle has been drawn on the work to indicate the required size the carrier, 15, will be '45 adjusted to bring the pin nearer and nearer to the grinding surface, 6*, as the work progresses until the piece has been worked down to circular form of the required radius. However, by providing the carrier, 15, with a zero mark, 15 and graduating the adjacent portion of the block, 14, as at 14", in terms of the distance of the pin from the grinding face of the disk, the carrier, 15, may be adjusted and work of the required radius produced thereon, without the necessity of marking the work, this being particularly useful in the case of duplicate or multiple work. The clamp for holding the carrier in adjusted position comprises a clamping shoe, 17 carriedin a guide-way, 14, so

as to approach the curved edge of the carrier, 15, at an acute angle, as indicated in Fig. 6. The shoe, 17, is swivelly connected to the end of'a screw, 18, by means of a pin,

, 17, engaging a circumferential groove, 18,

near the end of the screw member, 18. The screw, 18, is carried in the threaded aperture, 14 in the edge of the block, 14, its knurled head, 18 being accessible just outside the block; only a slight turn of the head, 18 is required for tightening or loosening this form of clamp.

The other attachment, which is illustrated in Figs. 7, 8 and 9, is in the nature of an adjustable comprising a base block, 19, in 5 which there is fixed a round stop or post,

20, and a threaded post, 21; a slotted member, 22, is mounted with its slot, 22 engaging the stud, 21,'and may be clamped as desired by means of a threaded wheel, 28, on 3 the stud, 21. It is intended that the stud, 20, and one end or other of the member, 22, shall serve as rests against which one edge of the work may be held for grinding an other edge at a given angle thereto, the g5 angle being determined by the position to which the member, 22, is adjusted. As shown in Fig. 7 the table is ruled with straight lines marked 30 degrees and 45 degrees, respectively, to which one of the 9 rounded ends of the member, 22, should be set tangent for producing 30 or 45-degree bevels. The remaining rulings shown in Fig. 7 are curved and are employed in producing the segmental parts of round builtup work, which forms a large portion of the pattern makers product. Such a segment is illustrated in Fig. 10, and is shown in dotted lines on Fig. 7 as placed on the work table against the stop, 20, and'the end, 22", of the adjustable member, 22. In this instance the circular work of which the segment, B, is a part, is to be ten inches in diameter, the segment comprising one-sixth of the circle. The stop shoulder, 22 and the stop, 20, being both tangent to the curve marked, 10, will serve as guides for the outer surface, B of the segment, B, while its ends, B are ground to the proper angle by the disk, 6; for the longer arc or for large work on the thirty-degree or forty-five-degree lines the opposite end, 22, of the member, 22, is designed to be used as a stop shoulder, being shown in full lines in Fig. 7 as set tangent to the twenty-one-inch curve. To permit use of this attachment even when the table 7, is tilted upward, the edge, 19 of the base block, 19, is beveled as shown in Fig. 9; the base block, 14, of the other attachment is similarly beveled at 14*, for the same pur 12o pose.

For many purposes a somewhat simpler device can be used in place of that just described. This consists of two guide members in the form of plugs, 24, each having a lower portion 24*, (see Fig. 11), adapted to fit any one of the holes, 15, in the circular and rotatably adjustable carrier, 15, as indicated in Fig. 3. If the piece of work such as the segment, B, shown in Fig. 10 has been carefully marked out so that the operator is grinding to the marks, he can rotate the carrier, 15, to a positionin which the guide plugs, 24:,serve to properly position the segment, B, or other piece of work just as. the post, 20, and guide member, 22, would do. Thecarrier, 15, being clamped in position by the clamp screw, 18, it will be evident that work of this nature can be rapidly. duplicated when the proper setting of the carrier has once been determined.

I claim 1. In agrinder comprising a rotary shaft, a grinding disk removably secured to one end of said shaft, and a work table adjacent to the face. of said disk, supporting means upon which the table is adapted to be held by its own weight, said means being open upwardly so that the table may be readily lifted off the support to permit removal of the disk from the said end of its shaft.

2. In a grinder comprising a rotary shaft, and a grinding disk removably secured to one end of said shaft, a work table adjacent to the face of the disk and having curved portions concentric about an axis approximating the intersection of the table plane with the face of the disk, and fixed supports curved to receive said portions, said supports being upwardly open and not more than semi-circular in extent, substantially as and for the purpose indicated.

3. In a grinder comprising a rotary shaft,

and a grinding disk removably secured to 7 one end of said shaft, a work table adjacent to the face of the disk andhaving curved portions concentric about an axis approximating the intersection of the table plane with the face of the disk, and fixed supports curved to receive said portions, said supports being upwardly open and not more than semi-circular in extent, said curved portions of the table having flanges overhanging the curved supports, and a clamp on one of the supports overhanging one of said flanges for securing the table at any position of adjustment about its axis.

4. In a grinder comprising a rotary shaft,

and a grinding disk removably secured to one end of said shaft, a work table adjacent to the face of the disk and having curved portions concentric about an axis approximating the intersection of the table plane with the face of the disk, and fixed supports curved to receive said portions, said supports being upwardly open and not more than semi-circular in extent, one of said curved portions having a notch in its periphery, and a bolt slidably carried on the corresponding support in position to be engaged in said notch at a particular angle of adjustment of the table.

5. In a grinder comprising a grinding wheel, and a work table adjacent thereto, a member carried by said table adapted to rotate about an axis perpendicular thereto,

and a work-holding pin on said member adapted to be moved toward orfrom the wheel by the rotation of said member.

6. In a disk grinder comprising a grinding wheel, and a work table adjacent there? to, a circular member rotatably mounted in the table with its plane surface flush with the tabletop, and a work-holding pin on said memberadapted to be moved toward or from the wheel by rotative adjustment of the member.

7. In a disk grinder comprising a grinding wheel, and a work table adjacent thereto, a circular member rotatably mounted in the table with 'its plane surface flush with the table top, a work-holding pin on said' member adapted to be moved toward or from the wheel by rotative adjustment. of

the member, and graduations on said member and on the surface of the table adjacent thereto adapted to indicate the distance of said pin from the grinding surface of the wheel at various positions of rotative adjustment of the member.

9. In a grinder comprising a grinding wheel, and a work table adjacent thereto,

a stop secured in the top of said-table near the grinding surface of the wheel, a series of lines ruled on the surface of said table and all tangent to said stop, a member havin a rounded end adjustably mounted on the table so that said end may be set tangent to any one of a plurality of said lines, and means for securing said member in adjusted position.

10. In a grinder comprising a grinding disk, and a work table adjacent thereto, a

stop secured in the top of said table near.

the grinding surface of the disk, a series of circular arcs inscribed on the surface of said table all tangent to the said post, and

having their respective centers located approximately in the grinding plane of the disk, a member having a rounded end adics justably mounted on the table so that said i end may be set tangent to any one of a plurality of said arcs, and means for securing said member in adjusted position.

11. In a grinder comprising a grinding wheel, and a work table adjacent thereto, a

post secured in the top of said table near the grinding surface of the wheel, a series of lines ruled on the surface of said table and all tangent to said post, a second post set in the table, a longitudinally slotted member having a rounded end and engaging said second post in its slot whereby its rounded end may be adjusted tangent to any one of a plurality of said lines, and clamping means on the post for securing said memloer at adjusted position.

In testimony whereof, I have hereunto 10 set my hand at Chicago, Illinois, this 17th day of November, 1915.

JOHN A. MoINTOSI-I.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0. 

